This relates generally to integrated circuits, and more particularly, to integrated circuits with configurable inductors.
Integrated circuits often have inductors. Inductors may be used in oscillators. For example, inductors may be used in LC-based voltage controlled oscillators for circuits such a phase-locked loops. LC-based voltage-controlled oscillators (e.g., voltage-controlled oscillators that include inductors and capacitors) may exhibit high quality factors and desirable phase noise and jitter performance in comparison to ring-based voltage-controlled oscillators.
The operating frequency range of a phase-locked loop may be limited by the frequency tuning range of its voltage-controlled oscillator. A conventional LC-based voltage-controlled oscillator generally has a fixed inductor (i.e., an inductor that has a fixed inductance value) and a varactor (i.e., a voltage-controlled capacitor). Because the value of the inductance is fixed, the frequency tuning range of the oscillator is limited by the amount of capacitance tuning that can be achieved using the varactor.
It would therefore be desirable to be able to provide improved inductor circuits such as inductor circuits that are able to exhibit adjustable inductances.